This is a subject I need a great deal of education in -- I'm glad to see such a comprehensive article on the subject!

Turnabout's fair play.

many thanks, GB

...let me ask you a question. If someone worked entirely in sRGB to produce a print, under what circumstances might working in a different color space result in a "significantly better" print?

Am I to assume here that the shot was taken as a jpeg in sRGB, or are we shooting raw?

RAW, of course. What's jpg, by the way?

If it starts out life as an 8-bit sRGB jpeg, there isn't much sense in going anywhere else.

If you've shot raw and your printer has a gamut larger than sRGB, then you'll do better, when processing images that have saturated red, oranges, and/or blues, using a wider space, at least Adobe RGB. This would often be the case for your red roses or dayglo orange graffiti or cobalt blue underwear.

If you've got a wide-gamut monitor that is capable of a broader gamut than sRGB (otherwise forget it), you can see just what is likely to happen by opening your Adobe RGB-processed file in PS, duplicating it and soft proofing the duplicate using the sRGB profile.

So, unless your monitor can work in a colorspace other than sRGB, you're better off just staying in sRGB? That is, can't the RAW converter and/or editor work in aRGB and approximate the results on an sRGB monitor, yet still retain the advantages of working in a larger color space? Or are you saying that unless your monitor can display the larger color space, any conversion or editing you do in sRGB will be counterproductive?

No, not really - at least if you're processing for print and your printer can outstrip sRGB to some degree. But then your limited monitor will have you flying somewhat blind in the processing and will only be able to see the effects after the fact in the print.

Toggling between the two will give you an idea of what is possible. Or, even more simply, use the Convert (to sRGB) dialog and toggle the Preview checkbox. If you see no important changes, then using the wider gamut hasn't bought you much, if anything.

I'm not sure what you're saying here. How do you toggle between colorspaces if your monitor can only handle sRGB? Or are you saying toggle between color spaces on a monitor that can display both color spaces?

Yes, the latter.

Clearly, if your monitor's gamut is roughly sRGB, you'll not be able to see any effect even if it exists. This is even more true for a gamut like ProPhoto RGB. No monitor is going to let you see a lot of what might be happening by using this space. Similarly, if your printer's gamut is close to sRGB, there is not likely to be any advantage in using a wider working space. The conversion will be done by the printer's profile and you'd be better off controlling it yourself prior to printing.

Sounds to me like what you're saying is you should only work in the colorspaces that are common to all the devices in the imaging chain. Is this correct?

As indicted above, if the printer has a gamut larger than the monitor, you might try, somewhat blindly, to take advantage of it. Some computer monitors have a really poor gamut, much less than a good inkjet printer. That combination would clearly put you at a real disadvantage, and I suspect it's not all that uncommon.

And, of course, you're always flying blind to some degree in using ProPhoto RGB (or LAB) because even the best of monitors can't really deal with the entirety of those spaces. That being said, I've certainly had a stretch where I used ProPhoto RGB almost all the time and printed out of that working space with great success.

And, by the way, it gets messier than that because monitor/printer gamuts rarely just encompass one another. The monitor may be broader than the printer in some color dimensions and narrower in others, and vice versa.

I've got a number of sunset shots with saturated oranges that I've processed with both sRGB and Adobe RGB, and the differences are quite noticeable from my Canon PixmaPro 9000 II (particularly when using Red River papers). The sRGB results are dull and disappointing.